1. Field of the Invention
The present invention relates to programmable controls for performing operations by agricultural vehicles traveling over a field surface.
2. Prior Art
Vehicle operation control systems that operate from programs for performing one or more tasks have been advanced in the art, as shown in U.S. Pat. No. 4,013,875, which has a programmed digital computer or microprocessor that contains a program to operate earth-engaging elements, such as an earth-working tool that may be a rotary, oscillatory, or linearly moveable earth-working tool for performance of given operations. An electromechanical actuator is used for operating the tool.
The device has manual override, but it does not teach precise positioning of the vehicle in relation to a position in the field, and does not teach the ability to repeat the program to perform the operation at previously programmed locations automatically even when visual clues, such as weed growth in need of spraying, are not present.
U.S. Pat. No. 4,744,207 shows a device for operating a cotton compactor on a cotton picker. The inventive concept in this particular patent is a teaching-following program where initially the program is placed into a learn mode, and the operation of the compactor controller is repeated as the unit subsequently is worked. Various sensor inputs for the prime mover itself are used and adjustments, such as "light yield" and "heavy yield" adjustments, can be added to the program for operating the compactor after the selected number of parameters are met.
Straight robotic control for various vehicles or prime movers also has been advanced. For example, the device shown in U.S. Pat. No. 4,674,048 is a robotic system that can be used for moving a vehicle around an obstruction.
U.S. Pat. No. 4,354,339 shows a program for steering and cutting blade control apparatus for a self-propelled lawn mower, utilizing a sensor and drive system that steers the lawn mower and controls the cutting blades through a nylon tape-type control input operating micro switches. The programming is accomplished by having various switch positions programmed on the tape for the desired operations.
Controls which include sensors for steering and operating vehicles are shown in U.S. Pat. Nos. 4,628,454 and 4,626,993.
Additionally, various electronic consoles have been used for controlling sprayers and other devices, and it is common to have speed sensors utilizing either magnetic sensing devices on a driven or non driven wheel, or ultrasonic signals. These also can calculate distance traveled, when the diameter of the wheel is correlated to the revolution of the wheel.
Devices for controlling sprayers and for determining speed are illustratively disclosed herein, and such devices are made and sold by a variety of companies. Thus, these components are shown only schematically herein.